Boat propelling mechanism



1937- v D. G. CHANDLER ET AL 2,096,223

BOAT PROPELLING MECHANI SM Filed Aug. 12, 1936 INVENTORSJ Ufl W0 6. CI/HNDLER ROBE T T SVf/VUSEN ATTORNEY.

Patented Oct. 1 9, 1937 UNITED STATES 2,096,223 7 BOAT PROPELLING MECHANISM' David G. Chandler and Robert T. Svendsen, Minneapolis, Minn.

Application August 12, 1936, Serial No. 95,560

* 9 Claims.

Our invention relates to outboard propelling units for boats, and the primary object is to provide an efficient, practical, and comparatively simple and rugged design of drive unit assembly which is especially an improvement over the general type of mechanism as disclosed in the copending application Ser. No. 702,920, filed by Robert T. Sven-dsen (one of present applicants) for Boat propelling mechanism.

More particularly a further and more specific object is to provide the unit with an anti-cavitation plate which is disposed, at an angle, forwardly inclined with respect to the horizontal, so as to best utilize the action of the water passing into the usual initial swell in the wake behind the boat, to hold the unit down in operative position and thus counteract the normal tendency of the propeller to lift forwardly out of the'water. A further object is to incline the cavitation plate laterally to both sides from its median line, or as seen in cross section, whereby listing of the vessel, as when making a turn, will not cause one side, of the plate to lift out of the water to thereby lessen or destroy its anti-cavitating function. A further object is to provide a novel and efficient method or means for manually adjusting and holding the drive unit at various elevations and for raising it to a completelyinactive, vertical position for inspection, repair, or removal. A further object is to provide a novel arrangement of cooling means in conjunction with the drive unit assembly for cooling water circulated from the cooling system of the engine or motor that drives the propelling mechanism. These and still other more detailed and specific objects willbe disclosed in the course of the following specification, reference being had to the accompanying drawing, wherein:

Fig. 1 is a left hand side elevation of our improved drive mechanism, as applied to the stem or transom wall of a boat, and with the major portion of the unit in sectional elevation for purpose 'of illustration.

Fig. 2 is a detail plan view of the lift lever retaining bar, as on line 22 in Fig. 1.

Fig. 3 is a transverse sectional elevation on line 31-3 in Fig. 1.

Fig. 4 is a detail elevation of a portion of the unit, as viewed from the right hand side.

Referring to the drawing more particularly and by reference characters, 5 designates the drive unit mounting plate, which is secured in and to the transom wall 6 of the boat I, in the manner more fully disclosed in the aforesaid menand lower bearings, I3 and M,'in a cast frame or housing I5, the upper or forward end of which is bifurcated and pivotally secured, as at iii, to two transversely spaced lugs ll extending integrally and rearwardly from the plate 5.

of universal joint It so that power can be transmitted freely while the frame If; is vertically adjusted, and this condition also permits the frame to be swung upwardly to or beyond a vertical position for repair or inspection purposes.

The frame is vertically adjusted, within certain limits, by a hand lever i8 which pivots, as

at I9, to a casting 26 to permit slight transverse adjustment of the lever and thereby facilitate engagement and release thereof with respect to spaced hooks or teeth 2| of an arm 22 extending rearwardly from and rigidly with respect to the plate 5. The casting is mounted for oscillation on one of the pivot pins 16 and has a laterally projecting lug 23 for engaging underan edge of the frame to lift andsupport the latter. The lever arm l8 has freedom for only limited rearward movement, however, and consequently when it is desired to swing the frame up to its vertical and completely inactive position it is grasped by hand and pulled forward to thus disengage from the lug 23 and to swing independently of the members I820.

The frame [5 includesa long integral fin 24 which extends downwardly and rearwardly,ter minating in a shoe 25 under the propeller I 2.

'This fin, and its shoe, serve not only to reinforce the frame, but also serve as a propeller guard so that the propeller will not become damaged by striking against obstructions in the water; The shoe portion 25 further serves as a bearing support and guard for the lower end of the rudder, 26.

and because of their particular form and position in the water willrideor pass over such obstructions, and when doing so will carry the pro- The pivot center Hi is axially aligned with the center 7 The fin and shoe additionally serve the useful and important purpose of initially contacting submerged obstructions such as rocks and logs,

' cally disposed reinforcingrib 29. The upper end 29, asfat 34. s

the sleeve 32, and when rotated operates through. the gear members 3l to angle the rudder in.

. thepropeller.

'turned by a suitable control device within the peller and rudder up out of destructive contact with such obstructions or objects. r

7 The upper end of the rudder ZBis'jQurnaled, as at 2], in anrearw'ardly extending, integral portion ofthe frame ilk-which portion includes .ananticavitation plate 28, and a central; vertieither direction to steer the vessel as maybe de 'sired. The sliding action'zof :the shaft .35 in sleeve 32 ,permits 10f vertical.fiuctuationsof the frameil5, while the boat is being operated, and

also permitsthe complete raising of the name toinactive position, without disrupting theibp-Q erative association of the shaft withrespect to The upper end'of the shaft is boat; operating through a horizontal shaft and the shaft '35 is provided with a, resilient collar 231 which is adapted to; abut against the sleeve 32 and thereby limits the downward movement of the'frame. IS with respect'to the boat and thewater level. V r

s We have provided means for lowering the temperature of the engine cooling fluid medium in' f V the formof, a chamber 38, arranged within or Attentio n is now directedto the form, incli adjacent the housing 15.", This chamber is 'confnected by inlet and outlet conduits 39 which lead system of the power 'su'pplying;engine. As the chamber f38'is subjectedto-the cooling action of "the water on which the craftgfloatsthe engine cooling medium is cooled'lwithout :drawinglake jjwater into the system which is objectionable be cause of the -cloggi'ng' which; frequently occurs J under such circumstances. It may be noted that the conduits 3 9 are flexiblefat least in. part, to

permit of the necessary vertical movements of the'framewhen swung on theaxis l6.

' z nation, and other characteristics of the 'anticavitationplateZB, all of which constitute: substantially important features of the present inven- 7 'tion. It will first be noted that the plate slopes 7 the .watertraveled throughtoeXert a downward or inclines downwardly," or at 'a' forwardxan'gle aWlth respect to thehorizontal; and thatits'for ward end is disposed at a point or level below the bottom of the sternend of;the boat. The pure pose of this arrangement is to cause the force of pressure. on the frame: [5,, and which pressure qwill. in turn counteract the normaltendency of aout Q the water.

t e prope lerto t t e. ame d boat s e also of cours e operates' in a known manner to' prevent or. effectively resist the 'water'cavitatin tendency of the'propeller. In:Ei g.' 1 of the drawing we have illustratedby; dotted lines the. general {contour of the water surface under varying con- 7 lditions. 7 Thus line A de'signates the normal ho'rie z ontal water surface when the boat isfat rest;

f Line B indicates the contour of the swell or wave followingain the wake of theboat when traveling atamedium or average speed; and line, C indicates the more elongated'swell as' it occurs under relatively highfspeed conditions. .Thus the positioniand formjof the swell with respect to the boat will depend upon the'character and a universal'joint 36. The lower'or rear end of.

protect by Letters Patent is 3 V H s or a boat having an inboard motor, comprising an1outboard frame-" normally disposed in an inclined position rear i V wardly of the boat andpivotally attached thereto;

. soas to be swingable in a'vertical plane parallel to. and through the plate 5 of the transom wall 6 and connect with the usual water circulation,

liftingtendericyof-the angularly disposed' 4 V speller andthefimpact of the water again's f housingpg 7 Wh l 0. .doin the plat 'relatively rearwardfwaterpressureto 'dowpward pressure to thereby counteract. the r orlmalter'idi 1 ency of the frame to rise.

speed of the boat, but in any event the forward angle of the anti-cavitation'plate is such as to fully and'properly utilize the (relative) water current'to obtain the required downward pressure on the frame as the boat travels forwardly Q under. the actionof the propeller.

It will be noted with particular rerrsce';-t 1 Fig. 3,'that'the plate 28' slopes; laterally andlto I both sides from its; median line attachment to the lower end o'f ribpcand awhile: the :blat'ekis here' shown as arcuate in cross sectiom substantially the same effect may. behad by merely inclining two plane plate sections; In eitherevent'the fobject is to prevent the plate from laterally projecting, above 'thefwater surface when, the boat is beingjturned, at whichtime the list of the boat has atendency totransversely tilt the plate, and.

this in turn greatly reduces the anti-cavitating properties of the plate; But by angling or de pressing the sideedges of the plate the objection thuscaused by listing or'tilting of; the' boat largely overcome;

It is understood that suitablemodifications maybe made in the structure asdisclosed, prof vided such modifications comewithin' the spirit and'scope of the appended claims. 'Havingpnow therefore fully illustrated and described our invention, what we claim't'o be new and desire to 7 1. A'propulsion apparatus.

with the direction of travel, a propeller-carried by the rear'end of the frame, drive connections a extending'from the propeller tothe motory af V rudder carried by and, angularly adjustable with respect to the frame, and ahanticavitationplate' carried by the frame aboveand forwardly of; the

propeller, said plate when inqnormal operative positionhaving its forward-end disposed= at-" a llower level than the rear end.

2. An outboard drive unit fora boat compris -Q ing aframe pivotally secured to and 'ex'tendin'g' rearwardly fromthe boat'fo'r vertical adjustment with respect thereto; a propeller shaft m'ounted in-the frame and'having a propellersecured'uponi the rear end thereof, theaxis of-said shaft and V propeller being operatively: disposed at anacute normally sloping, forward ana downwardly whereby when the boat? moves forwardlyfthe action of the water on the plate. will" produce a downward pressure on the frame tofc'ounteract the 7 f3. Anoutboardidrive unit for aboat cempris' ing apropeller shaft extending :ati anjang le down: .Wardly and rearwardly fromthe rear of the boat, 7 a propellercarriedflby the-rear end of the'sh'aft 'for rotati'on'about the inclined axis thereof means I or mounting the shaft permitting; vertical fluctuations of the propeller end thereof; and a rearwardly and upwardly inclined plate associated; v with" the mounting means for travel movment belowthe water surface and for convertingth'e r. An outboard 'drive unit for a boat combris- "ing a propellerjshaft eitending-at' an angledown- 7-5 7' s01 anglewith respect to thehorizontaLan'd a plate carried byfthe frame for" engagement inthepi water' and disposed forfoperation atfan angle wardly and rearwardly from the rear of the boat, a propeller carried by the rear end of the shaft for rotation about the inclined axis thereof, means for mounting the shaft permitting vertical fluctuations of the propeller end'thereof, and a rearwardly and upwardly inclined plate associated with the mounting means for travel movement below the water surface and for converting the relatively rearward Water pressure to downward pressure to thereby counteract the normal tendency of the mounting means to rise when the propeller is in motion, said plate being disposed above and forwardly of the propeller so as to serve as an anti-cavitation member with respect thereto.

5. An outboard drive unit for a boat having an i-nboard power plant, comprising a frame member pivotally attached at its forward end to the stern of the boat so that its other end may be moved vertically in a plane parallel with the direction of travel, a propeller and a rudder at the rear end of the frame, a rudder operating shaft disposed above and in general parallelism with the frame and having a sliding connection with the rear end of the frame, said shaft having means forming a stop to limit the downward movement of the frame in the water.

6. An outboard drive unit for a boat having an inboard power plant, comprising a frame member pivotally attached at its forward end to the stern of the boat so that its other end may be moved vertically in a plane parallel With the direction of travel, a propeller and a rudder at the rear end of the frame, a rudder operating shaft disposed above and in general parallelism with the frame and having a sliding connection with the rear end of the frame, said shaft having means forming a stop to limit the downward movement of the frame in the Water, and said stop means being of a resilient character to cushion the supporting action of the shaft with respect to the frame.

7. An outboard drive unit for a boat, comprising an inclined frame member pivotally attached at its forward upper end to the stern end of the boat and having a propeller at its rear end for operation at a relatively lower level in the water back of the boat, and means for vertically adjusting the frame comprising a lever extending upwardly from the frame, and a toothed arm projecting rearwardly from the boat for releasable engagement by the lever.

8. An outboard drive unit for a boat, comprising an inclined frame member pivotally attached at its forward upper end to the stern end of the boat and having a propeller at its rear end for operation at a relatively lower level in the water back of the boat, and means for vertically adjusting the frame comprising a lever extending upwardly from the frame, and a toothed arm projecting rearwardly from the boat-for releasable engagement by the lever, said lever having freedom for limited transverse movement.

9. An outboard drive unit for a boat, comprising an inclined frame member pivotally attached at its forward upper end to the stem end of the boat and having a propeller at its rear end for operation in the water back of the boat, and means for vertically adjusting the frame comprising a lever extending upwardly from the rear end of the frame, and a toothed arm projecting rearwardly from the boat for releasable engagement by the lever, said frame being disengageable with respect to the lever whereby the frame may be swung upwardly and forwardly beyond the position of lifting limit of the lever.

i DAVID G. CHANDLER.

ROBERT T. SVENDSEN. 

